Method and apparatus for controlling power supplied to a receiver based on detection of errors in groups of data in a signal being received by said receiver

Abstract

A synchronization controller identifies the timing of the group assigned to the receiver based on a synchronization signal detected by a preamble and synchronization signal detector. At this timing the power supply of a radio section is turned on. A selective calling number within the received group and pre-assigned selective calling number are compared in a selective calling number detector. The power supply of the radio section is immediately turned off, if the result of the comparison is non-coincidence. In this way, the battery saving efficiency can be enhanced by arranging to turn on the radio section only in the groups which are assigned to the receiver, and turning off immediately the power supply of the radio section when the receivers assigned selective calling number is not found in the receiver's assigned group.

What is claimed is: 
     
       1. A receiver with a power supply control feature for a radio section responsive to signals containing a preamble and multiple batches, each batch containing a synchronizing signal and multiple codeword groups, said receiver being assigned to at least one of said groups, comprising: means for detecting a first synchronizing signal included in one batch;   means for detecting an error of the group assigned to said receiver after detecting said first synchronizing signal;   means for preventing power application to said radio section at timings of synchronizing signal receptions after a detection of said first synchronizing signal and when a number of said error is lower than a predetermined amount; and   means for turning on said radio section on detection of said first synchronizing signal, and at reception timings of the group assigned to said receiver when the number of said error is lower than a predetermined amount.   
     
     
       2. The power supply control as claimed in claim 1, wherein each said group contains a selective calling number, said power supply control further comprising: means for turning off said radio section when selective calling number in the receiver's assigned group is not the same as a selective calling number assigned to said receiver.   
     
     
       3. A receiver comprising: first detecting means for detecting a first synchronizing signal following a preamble signal in a received signal, said received signal including said preamble and a plurality of batches, each batch consisting of said synchronizing signal and several groups which include first and second codeword blocks;   first control means for generating a first timing signal at the timing of each group assigned to said receiver within said received signal, and for turning a radio section in said receiver on in response to said first timing signals and for maintaining said radio section off at reception timings of synchronizing signals after said detection of said first synchronizing signal;   second detecting means for detecting a selective calling number in one of said codeword blocks, said receiver being assigned a particular selective calling number;   error checking means for checking a block error in an error correction code received in said blocks; and   second control means for turning said radio section off in response to no detection of said particular selective calling number and detection of a result of no block error.   
     
     
       4. The power supply control as claimed in claim 3, wherein said second control means comprises: latching means for latching a result of said block error for one codeword block;   an AND gate for inputting said result of said block error and a signal indicating said detection of said particular selective calling number; and   supplying means for supplying a battery saving control signal to said radio section to turn off when said particular selective calling signal is not detected and no block error is detected.   
     
     
       5. The power supply control as claimed in claim 3, further comprising monitoring means for monitoring a bit rate of said received signal; and third control means for turning said radio section off when said bit rate of the received signal is different from a predetermined rate.   
     
     
       6. The power supply control as claimed in claim 3, further comprising first generating means for generating a regenerated clock based on a reference clock and said received signal and for supplying said regenerated clock to said first detecting means and said first control means as a operation clock. 
     
     
       7. The power supply control as claimed in claim 6, wherein said received signal comprises said preamble and a plurality of batches, each batch consisting of said synchronizing signal and several groups which include first and second codeword blocks, said first control means comprises: second generating means for generating a second timing signal at a timing of each said group based on said regenerated clock and said detection of said first synchronizing signal; and   third generating means for generating said first timing signal in response to said second timing signal.   
     
     
       8. The power supply control as claimed in claim 3, wherein said first control means turns said radio section on before the reception timings of said assigned groups. 
     
     
       9. A method for controlling a power supply to a radio section in a receiver, the method comprising the steps of: detecting a first synchronizing signal followed a preamble signal in a received signal;   generating a first timing signal at the timing of groups assigned to said receiver within said received signal;   detecting an error of a pre-assigned group in said received signal;   turning a radio section in said receiver on in response to said first timing signal; and   keeping said radio section off at reception timings of synchronizing signals when the error is below a predetermined level, after said detection of said first synchronizing signal.